<div class="input-group ">
<div class="input-group-prepend">
  <span class="input-group-text" id="basic-addon1" >用户名</span>
</div>
<input type="text" class="form-control" placeholder="请输入用户名" aria-label="Username" aria-describedby="basic-addon1" [(ngModel)]="username">
</div>

<div class="input-group mb-3">
<div class="input-group-prepend">
  <span class="input-group-text" id="basic-addon2">密码</span>
</div>
<input type="password" class="form-control" placeholder="请输入密码" aria-label="Username" aria-describedby="basic-addon2" [(ngModel)]="password">
</div>


<button class="btn btn-primary" (click)="login()" >登录</button>
